CORE Metadata, citation and similar papers at core.ac.uk Provided by CMFRI Digital Repository /. mar. biol. Ass. India, 1984, 26(1 & 2) : 109-122 STUDIES ON INDIAN ECHINODERMS - 15. ON PSOLUS MANNARENS1S SP. NOV. AND OTHER DENDROCHIROTIDS FROM THE INDIAN SEAS* D. B. JAMES** Central Marine Fisheries Research Institute, Cochin-682 031 ABSTRACT In this paper eleven species of Dendrochirotids belonging to eleven genera are described. Pnolus campla- natus deposited in the Madras Museum on re-examination was found to be a new species and is described here as Psolus mannarensis. Notes on the habits of some of the species is given for the first time. Remarks on zoogeography are added at the end of the paper. INTRODUCTION ORDER : DENDROCHIROTIDA Members of this Order have branched ten­ INFORMATION on the Dendrochirotids is very scanty and scattered due to their restricted tacles which lack conspicuous ampullae. Gona- dial tubules are arranged in two tufts on either distribution. In this connection mention may side of the dorsal mesentery. Respiratory trees be made of the papers of Bell (1889), Thurston present, but Cuvierian tubules are absent. (1890), Koehlar and Vaney (1908), Gravely (1927, 1941), Chhapgar (1962), James (1969, Members belonging to three Families are 1983, 1985) and Mary Bai (1980) where some known from the Indian Seas. Species belong­ Dendrochirotids are listed. The author has ing to all the three Families have been collected. described four species in detail from the Gulf of Mannar (James, 1965, 1966, 1975). In the KEY TO THE FAMILIES present paper detailed descriptions of the other species with notes on the habits are given. 1. Ventral surface modified into a creeping Some remarks on the zoogeography of the sole; dorsal surface naked with large scales; species are given at the end of the paper. tentacles usually ten, two midventral ones small; calcareous ring simple without post­ The author is grateful to Dr. S. Jones, for­ erior prolongations Psolidae mer Director of C. M. F. R. I. for suggesting the problem and supervising the work and to V. Ventral side not differentiated into sole; Dr. P. S. B. R. James, Director, C. M. F. R. scales absent; tentacles 10-30 2 Institute, Cochin for the kind interest and encouragement in the work. I also thank Dr. 2. Tentacles ten in number arranged in a S. T. Satyamurty, former Director of Madras single circle; ambulacral appendages us­ Museum for kindly permitting me to re-examine ually restricted to ambulacra; calcareous the Dendrochirotids in the Museum. ring usually simple without posterior pro­ longations Cucumariidae * Formed a part of the Ph.D. thesis, Andhra Uni­ 2'. Tentacles more than ten arranged in two versity, Waltair. circles; ambulacral appendages usually ** Present address : MRC of CMFRI, Madras-105. distributed all over the body; calcareous 110 D. B. JAMES ring with many pieces and prolongations to 0.109 mm and breadth varies from 0.047 to Phyllophoridae 0.078 mm. Irregular buttons lack knobs. 4 to 11 holes at the centre of buttons, usually four. i Family : Psolidae This family has one genus Psolus represented Supporting plates: Present in pedicels; fusi­ in the Indian Seas. form in shape with large holes at centre and smaller ones at ends. Usually four large holes Genus Psolus Oken at centre. Length of supporting plates varies from 0.125 to 0.251 mm and breadth varies Psolus camplanatus Semper was reported from 0.047 mm to 0.094 mm. from the Gulf of Mannar by Gravely (1927) and Satyamurty (1976). This specimen depo­ Linear bodies: Fusiform in shape with four sited in the Madras Museum, has been re-exa­ or five bands over them. Length of linear bod­ mined by the author and was found to be ies varies from 0.062 to 0.125 mm and breadth different from P. camplanatus. It is described 0.031 mm. here as a new species. Gravely (1927) has stated that the colour is Psolus mannarensis sp. nov. (Fig. 1 a) mottled dark greyish above and whitish on the ventral side. Psolus camplanatus Gravely, 1927, p. 166: Gulf of Mannar. Satyamurti, 1976, p. 38: Pamban (Gulf of Mannar.) (Non P. camplanatus Semper, Remarks: The present species is closely relat­ 1868. ed to P. complanatus in its form and arrange­ Material: Pamban (Gulf of Mannar) 1 speci­ ment of pedicels. However the spicules are men. different. It also differs from P. boholensis in the absence of rosette like spicules. The regular Description: Length 15 mm. Body very much buttons and the linear bodies are characteristic flattened and depressed. Tentacles ten in num­ of the present new species. It is named after ber and fairly well extended. In lateral ambu­ its area of collection. lacra there are four to six rows of pedicels and in the middle one, two or three complete rows. Family : Cucumariidae On dorsal side of body 14 to 16 scales across the body. Between mouth and cloaca 10 to 12 Twelve genera are known from the Indian Seas of which six are collected and described large and small scales. Scales slightly granu­ in the present paper. lated. Calcareous ring has ten pieces which are KEY TO THE GENERA abruptly truncated at distal end. Radials are longer and deeply notched at middle. Interra- 1. Calcareous ring without posterior prolon­ dials stout and pointed anteriorly. gations 2 Spicules (Fig. 1 a) are of three types : buttons, 1'. Calcareous ring with distinct posterior supporting plates and linear bodies. prolongations ; 4 Buttons: Both regular and irregular types, 2. Body elongated, curved and pentagonal present in sole. Regular buttons oval in shape with double rows of pedicels and single with 8 to 10 knobs. Usual number of knobs row of papillae along each ambulacrum; ten. At centre of buttons there are four holes. body wall firm Length of regular buttons varies from 0.047 .........Leptopentacta H. L. Clark, 1938. STUDIES ON INDIAN ECHINODERMS -15 HI Fig. 1 a. Spicules of Psolus inannarensis sp. nov., b. Radial and interradial plates of Pentacta quadrangularis, c. Tubefeet, d. spicules of P. quadrangularis, e. Body wall spicules of Afrocucumis africana; Tubefeet spicules of A. africana; g. Radial and interradial plates of A. africana; h. Radial and interradial plates of Phyrella fragilis; i. Spicules of P. fragilis and j. Radial and interradial plates of Havelockia versicolor. 21. Body robust with pedicels arranged in 3. Body quadrangular in cross section; pedi- | three rows or bands on the ventral side; eels in three bands on the flattened ventral ! | body wall not firm 3 surface; papillae usually large and conical 112 D. B. posterior, end fiiore pointed than anterior end. ^...Pentacta Goldfuss, 1820 Podia a'franged in five rows, but not dense in distribution. In larger specimen 22 pedicels 3'. Body cticumber-like; pedicels in three in a row. Tentacles ten in number of which distinct rows ventrally; papillae small and ventral two small. Calcareous ring has no scattered donally posterior prolongations. •,....Pseudoeolochirus Pearson, 1910 Spicules (Fig. 2 a) consist of smooth buttons 4. Pedicels generally restricted to double rows mostly with four holes. Some of buttons are on the ventral side; body pentagonal in roughly circular or irregular in shape with five cross section • • to sevein holes. Hemiihyone' Pawson, 1963 Distribution: It is known from the South East 4'. Pedicels and papillae not restricted to rows Arabia, Maldives, Bay of Bengal and East or bands body circular in cross section Indies. It is reported here for the first time j..'. 5 from the Arabian Sea. 5. Posterior prolongations of calcareous ring Genus Pentacta Goldfuss, 1820 with many pieces Stolus Selenka, 1867 Three species are known under this genus from the Indian Seas of which one has been 5'. Posterior prolongations of calcareous ring collected and described in this paper. with fewer number of pieces Havelo ckia Pearson, 1903 KEY TO THE SPECIES Genus Leptopentacta H. L. Clark, 1938 1. Dorsal papillae in regular longitudinal series on ambulacra Only one species is known from the Indian P. quadrangularis (Troschel 1846) Seas. Leptopentacta javanicus (Sluiter) 1'. Dorsal papillae not in regular longitudinal (PI. I A; Fig. 2 a) series on ambulacra , 2 Oncus javanicus Sluiter, 1880, p. 9: Java. Ludwig, 2. Small baskets with ,knobs 1882, p. 134: Java. Bell, 1886, p. 27: Mergui ,.:......... P. ropusta (Ostergren, 1898) Archipelago. Oncus sp. Bell, 1884, p. 246: Port Darwin. 2'. Small baskets without \ kriobs P. cucumis (Semper, 1868) Leptopentacta javanicus H. L- Clark, 1938, p. 453. A.M. Clark &Rowe, 1971, p. 180. Mari Bai, 1980, p. 20. Price, 1982, p. 11: South East Pentacta quadrangularis (Troschel) Arabia. James, 1985, p. 580: Lakshadweep & (Fig. 1. b-d) Maldives. Colochirus quadrangularis Troschel, 1846, p. 84. (Non Material: Pamban (Gulf of Mannar) 1 speci­ Hobthuria quadrangularis Lesson, 1830, p. 90). Selenka, 1868, p. 112. Semper, 1868, p. 60: men; Neendakara (West coast of India) 1 speci­ Philippines. Theel, 1882, p. 121: Hong Kongt men. Siam, Australia. Ludwig, 1882, p. 131: East Indies. Bell, 1889, p. 7: Gulf of Mannar. Thur­ ston, 1890, p. 113: Gulf of Mannar. Thurston, Description: Length 30 and 45 mm. Body elon­ 1894, p. 115: Tuticorin (Gulf of Mannar). Pear­ gated and slender (PI. I A). Both specimens son, 1903, p. 196: Sri Lanka. Ekman, 1918, p. 21: Cape Jaubert. Panning, 1949, p. 446: stiff and curved. Body wall firm and rigid; Australia. D. 11 JAMES, PLATE i I A. •cuaimis africema and STUDIES ON INDIAN ECHINODERMS -15 113 O-lhH , Fig. 2 a. Spicules of Leptopentacta javanicus, b. Spicules from tubefeet of Hemithyone semperi, c. Spicules from bodywall of H. semperi, d. Spicules from young specimen of Stolus buccalu, e. Spicules of Stolus sp., f.